Control of coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) with botanical insecticides and mineral oils

Controle da broca-do-café, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) com inseticidas botânicos e óleos minerais

ABSTRACT.

The objective of this study was to evaluate botanical oils, mineral oils and an insecticide that contained azadirachtin (ICA) for the control of Hypothenemus hampei, in addition to the effects of residual castor oil. We evaluated the effectiveness of the vegetable oils of canola, sunflower, corn, soybean and castor, two mineral oils (assist^(r) and naturol^(r)), and the ICA for the control of H. hampei. The compounds were tested at a concentration of 3.0% (v v^-1). The median lethal concentration (LC₅₀) was estimated with Probit analysis. The oil of castor bean and extract of castor bean cake were also evaluated at concentrations of 3.0% (v v^-1) and 3.0% (m v^-1), respectively. The mortality rates for H. hampei caused by the ICA and the castor oil were 40.8 and 53.7%, with LC₅₀ values of 6.71 and 3.49% (v v^-1), respectively. In the castor oil, the methyl esters of the fatty acids were palmitic (1.10%), linoleic (4.50%), oleic (4.02%), stearic (0.50%) and ricinoleic acids (88.04%). The extract of the castor bean cake was not toxic to H. hampei. The persistence of the castor oil in the environment was low, and the cause of mortality for H. hampei was most likely the blockage of the spiracles, which prevented the insects from breathing.

Keywords:
Ricinus communis; Azadirachta indica; median lethal concentration; fatty acids, toxicity